| Abstract Submission No. | ABS-2.4-0086 |
| Title of Abstract | Forward Modelling of Anomalous Magnetotelluric Phase Data in Panamik-Changlung Hotsprings Region, Ladakh |
| Authors | Venkata Durga *, Prasanta K Patro, Dhamodharan S, Abdul Azeez K K |
| Organisation | CSIR-National Geophysical Research Institute, Hyderabad, India |
| Address | CSIR- NGRI Habsiguda, Telangana, India Pincode: 500007 E-mail: devinamu2940@gmail.com |
| Country | India |
| Presentation | Oral |
| Abstract | The Panamik geothermal field in Ladakh, one of the most prominent geothermal systems in the Nubra valley, between the Karakoram Fault (KF) and the Shyok Suture Zone (SSZ) in the Trans-Himalayan region of Ladakh. This region has not yet been mapped well with geophysical methods. We acquired Broadband (BBMT) and Long-Period (LMT) measurements at 34 locations covering a 30 km profile, which crosses the Panamik and Changlung hot springs. We analysed the data, and predominantly, a cluster of sites shows anomalous phases along the profile. This anomalous behaviour mainly arises due to current channelling and anisotropy effects of the subsurface formations. Current channeling from near-surface inhomogeneous effects can reverse or distort the direction of electric fields. Additionally, electrical anisotropy in layered materials can create similar distortions. Traditional inversion methods, with this data may give rise to an unrealistic subsurface picture. To address these issues, an anisotropy modeling and current channeling approach is necessary for accurate subsurface conductivity mapping. Hence, we have conceptualized a forward model mimicking the geology and tectonics of this region. Initial modelling studies suggest the possibility of an L-shaped conductor in this region, giving rise to phase out of quadrant behavior. However, we are also studying an alternative possibility of micro anisotropy at the upper crustal depths. We present these scenarios and discuss the genesis of anomalous phases in the Panamik geothermal region. These analysis leads to clearer interpretations and improve the accuracy of subsurface conductivity mapping, strengthening the identification of geothermal targets. |
| Keywords | Magnetotellurics, Panamik-Changlung Hotsprings, Anomalous Phase, Current channeling, Anisotropy |